scholarly journals PL Tunable GaN Nanoparticles Synthesis through Femtosecond Pulsed Laser Ablation in Different Environments

Nanomaterials ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 439 ◽  
Author(s):  
Juan Hao ◽  
Sijia Xu ◽  
Bingrong Gao ◽  
Lingyun Pan
Keyword(s):  
Laser Ablation ◽  
Photoelectron Spectroscopy ◽  
Pulse Laser Ablation ◽  
Optoelectronic Devices ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Alternative Methods ◽  
X Ray ◽  
Pl Spectra ◽  
Bulk Gan

The tunable photoluminescence (PL) property is very important for gallium nitride (GaN) nanoparticles in the application of ultraviolet and blue optoelectronic devices, while conventional methods are not so satisfactory that alternative methods for preparing GaN nanoparticles should be studied. In this paper, ultra-small and well dispersed GaN nanoparticles are fabricated through femtosecond pulse laser ablation in air, water and ethanol. For the PL spectra of GaN nanoparticles, there are no shifts in air, red shifts in water and blue shifts in ethanol compared with the intrinsic PL spectra of bulk GaN. The X-ray photoelectron spectroscopy (XPS) results demonstrate that the various PL spectra can be due to the different components inside the GaN nanoparticles, which not only have effect on the PL emissions, but also greatly influence the intensity of PL. This study validates that the ablation environment has a great adjustable effect on the properties of GaN nanoparticles.

scholarly journals Deposit of AlN thin films by nitrogen reactive pulsed laser ablation using an Al target

2019 ◽  
Vol 65 (4 Jul-Aug) ◽  
pp. 345 ◽  
Author(s):  
F. Chale-Lara ◽  
M. Zapata-Torres ◽  
F. Caballero-Briones ◽  
W. De la Cruz ◽  
N. Cruz Gonzalez ◽  
...  
Keyword(s):  
Thin Films ◽  
Laser Ablation ◽  
Photoelectron Spectroscopy ◽  
Hexagonal Phase ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Nitrogen Pressure ◽  
Binding Energies ◽  
Xps Spectra ◽  
X Ray

We report the synthesis of AlN hexagonal thin films by pulsed laser ablation, using Al target in nitrogen ambient over natively-oxidized Si (111) at 600°C. Composition and chemical state were determined by X-ray photoelectron spectroscopy (XPS); while structural properties were investigated using X-ray diffraction (XRD). High-resolution XPS spectra present a gradual shift to higher binding energies on the Al2ppeak when nitrogen pressure is incremented, indicating the formation of the AlN compound. At 30 mTorr nitrogen pressure, theAl2p peak corresponds to AlN, located at 73.1 eV, and the XRD pattern shows a hexagonal phase of AlN. The successful formation of the AlN compound is corroborated by UV-Vis reflectivity measurements.

scholarly journals Influence of Titania Synthesized by Pulsed Laser Ablation on the State of Platinum during Ammonia Oxidation

2020 ◽  
Vol 10 (14) ◽  
pp. 4699
Author(s):  
Andrey Stadnichenko ◽  
Dmitry Svintsitskiy ◽  
Lidiya Kibis ◽  
Elizaveta Fedorova ◽  
Olga Stonkus ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Photoelectron Spectroscopy ◽  
Ammonia Oxidation ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Active Species ◽  
Laser Ablation In Liquid ◽  
X Ray ◽  
Catalytically Active ◽  
Physicochemical Methods

A set of physicochemical methods, including X-ray photoelectron spectroscopy (XPS), X-ray diraction, electron microscopy and X-ray absorption spectroscopy, was applied to study Pt/TiO2 catalysts prepared by impregnation using a commercial TiO2-P25 support and a support produced by pulsed laser ablation in liquid (PLA). The Pt/TiO2-PLA catalysts showed increased thermal stability due to the localization of the highly dispersed platinum species at the intercrystalline boundaries of the support particles. In contrast, the Pt/TiO2-P25 catalysts were characterized by uniform distributionof the Pt species over the support. Analysis of Pt4f XP spectra shows that oxidized Pt2+ and Pt4+ species are formed in the Pt/TiO2-P25 catalysts, while the platinum oxidation state in the Pt/TiO2-PLA catalysts is lower due to stronger interaction of the active component with the support due to stronginteraction via Pt-O-Ti bonds. The Pt4f XP spectra of the samples after reaction show Pt2+ and metallic platinum, which is the catalytically active species. The study of the catalytic properties in ammonia oxidation showed that, unlike the catalysts prepared with a commercial support, the Pt/TiO2-PLA samples show higher stability during catalysis and significantly higher selectivity to N2 in a wide temperature range of 200–400 C.

scholarly journals Continuous Synthesis of Ag/TiO2 Nanoparticles with Enhanced Photocatalytic Activity by Pulsed Laser Ablation

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Rui Zhou ◽  
Shengdong Lin ◽  
Huixin Zong ◽  
Tingting Huang ◽  
Fengping Li ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Electron Microscope ◽  
Laser Ablation ◽  
Photoelectron Spectroscopy ◽  
Uv Light ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Silver Clusters ◽  
X Ray ◽  
Synthesis Strategy

A facile and environmental friendly synthesis strategy based on pulsed laser ablation has been developed for potential mass production of Ag-loaded TiO2 (Ag/TiO2) nanoparticles. By sequentially irradiating titanium and silver target substrates, respectively, with the same 1064 nm 100 ns fiber laser, Ag/TiO2 particles can be fabricated. A postannealing process leads to the crystallization of TiO2 to anatase phase with high photocatalytic activity. The phase composition, microstructure, and surface state of the elaborated Ag/TiO2 are characterized by X-ray diffraction (XRD), energy dispersive X-ray (EDX), field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS) techniques. The results suggest that the presence of silver clusters deposited on the surface of TiO2 nanoparticles. The nanostructure is formed through laser interaction with materials. Photocatalytic activity evaluation shows that silver clusters could significantly enhance the photocatalytic activity of TiO2 in degradation of methylene blue (MB) under UV light irradiation, which is attributed to the efficient electron traps by Ag clusters. Our developed Ag/TiO2 nanoparticles synthesized via a straightforward, continuous, and green pathway could have great potential applications in photocatalysis.

X-ray spectroscopic and stroboscopic analysis of pulsed-laser ablation of Zn and its oxidation

2017 ◽  
Vol 124 (1) ◽  
Author(s):  
Stefan Reich ◽  
Jörg Göttlicher ◽  
Alexander Letzel ◽  
Bilal Gökce ◽  
Stephan Barcikowski ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
X Ray

Pulsed Laser Ablation of Tin Oxide Nanoparticles in Liquid for Optoelectronic Devices

Silicon ◽  
2020 ◽  
Author(s):  
Raid A. Ismail ◽  
Sule Erten-Ela ◽  
Abdulrahman K. Ali ◽  
Cagdas Yavuz ◽  
Khaleel I. Hassoon
Keyword(s):  
Laser Ablation ◽  
Tin Oxide ◽  
Optoelectronic Devices ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Oxide Nanoparticles ◽  
Tin Oxide Nanoparticles

Microstructure and Thermoelectric Properties of p-Type Bi0.5Sb1.5Te3 and n-Type Bi2Te2.7Se0.3 Films Deposited by Pulsed Laser Ablation

2001 ◽  
Vol 691 ◽  
Author(s):  
Raghuveer S. Makala ◽  
K. Jagannadham ◽  
B.C. Sales ◽  
Hsin Wang
Keyword(s):  
Laser Ablation ◽  
Thermoelectric Properties ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Uniform Thickness ◽  
X Ray Diffraction ◽  
High Crystalline Quality ◽  
X Ray ◽  
Crystal Perfection ◽  
P Type

ABSTRACTThin films of p-type Bi0.5Sb1.5Te3, n-type Bi2Te2.7Se0.3 and n-type with SbI3 doping were deposited on mica substrates using Nd-YAG pulsed laser ablation at temperatures ranging from 300°C to 500°C. These films were characterized using X-ray diffraction, SEM and TEM. X-ray mapping and EDS were used to determine the composition. The films showed uniform thickness and high crystalline quality with a preferred (00n) alignment with the substrates. The film quality in terms of composition and crystal perfection is studied as a function of growth temperature. It was found that films deposited at 350°C gave improved crystallinity and thermoelectric characteristics. The Seebeck coefficient, electrical resistivity and Hall mobility were measured as a function of temperature and compared with the measurements on the bulk. Correlation of thermoelectric properties with microstructure is discussed.

Growth of Epitaxial ZnS Films by Pulsed-Laser Ablation

1992 ◽  
Vol 242 ◽  
Author(s):  
J. W. McCamy ◽  
D. H. Lowndes ◽  
J. D. Budai ◽  
B. C. Chakoumakos ◽  
R. A. Zuhr
Keyword(s):  
Laser Ablation ◽  
Stacking Faults ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Temperature Dependent ◽  
High Quality ◽  
X Ray ◽  
Fault Density ◽  
Highly Uniform ◽  
Zns Films

ABSTRACTPulsed KrF (248nm) laser ablation of a polycrystailine ZnS target has been used to grow high quality, carbon-free, epitaxial ZnS thin films on GaAs(OOl), GaAs(111), and GaP(OOl). The films were grown at temperatures of 150–450°C, using a rotating substrate heater and deposition geometry that produces films with highly uniform thickness. X-ray rocking curves are consistent with (111) stacking faults being the dominant defects in the ZnS films grown on GaAs. The estimated stacking fault density is ∼6 × 1010 cm-3, comparable to the best MOCVD ZnS films. RBS analysis shows that these defects are located predominantly near the GaAs-ZnS interface. The anisotropy of the ZnS growth rate, between the GaAs(001) and GaAs(111) surfaces, was found to be temperature-dependent.

Sign in / Sign up

Export Citation Format

Share Document